Setting value for dropdown list to display from a parameter variable

[Anonymous]

Hi all,

This is a problem which is probably due to an inconsistency on my part but I can't spot why it works for two drop-downs and not for the third.

I have a canvas app form, where the user selects data from 3 drop-downs.  When submitting the chosen fields, the form checks to see if there is an associated record in a sharepoint list (these fields are mandatory in SP).  If there are then the record is displayed in the next form in Edit mode.  If the record can't be found then the same form is displayed but in displaymode.New.  

In this latter case, I want to display the three chosen drop-downs in view/disabled-only.  The way I'm currently setting the dropdown is by assigning what was chosen to variables in the OnSelect button of the submit button:

(in the default value property of DCV3 I have (DataCardValue4.Selected.Value & " - " & DataCardValue101.Selected.Value & " - " & DataCardValue102.Selected.Value)

When we get to MainScreen, I pass the variables to load some text labels.

I then decided that I want to just display the actual drop-downs (in view-only mode), that way when the record is submitted, I can be sure that all the (mandatory) fields have values.  So the top of the main screen now displays the values from the variables and the bottom is where I added the actual dropdowns and have the following code in the default property of the datacard:

 However as you can see, the first field (Operator) is not showing any value, even though the variable has a value (it is assigned to the text label on the top for operator:

Why is the lookup working for two fields but not for the first?

[Scott_Parker]

What is the column type of [Operator]? The Choices() function will function differently depending on the column type:

• If it is of column type Lookup, it will return all values in the Lookup list.
• If it is of column type Choice, it will return a combination of values actually present in the list plus the values specified in the column definition.
• If the column type is Text, it will only give you values which are already present in your list. Choices() just grabs the number of rows equal to your "data row limit" and gets a distinct list of values from that.

It boils down to where your full list of options is for the fields being kept. I personally use Lookup and Choice columns and keep it in SharePoint.

[Anonymous]

Thanks for replying but when I check out the columns themselves in SharePoint, they are all exactly the same:

arrrgh! Frustrating!

[Scott_Parker]

Okay, and does the Operator column have all of the choices defined in the SharePoint field?

Collect the value returned from Choices and then inspect the variable. Should give you some clues as to what is breaking:

Collect(colTemp, Choices(VS094OperatorEnergyData.Operator))

(add the above code to a button inside of your form).

[Anonymous]

Moving a little bit further forward with this.

Using the monitor I can see that the look-ups happen Operator first (row id 11):

Then site (row id15):

Then Month (row id: 17)

However in between row 11 and row 15, the code for the submit button from the previous screen is called:

So for some reason, when the next screen is called, the look-ups are executed for those drop-downs on the new screen but the operator check is done before the code from the submit button is executed.  This is where the values for the variables are set (see first screenshot in original post).  The operator look-up call happens before this code is executed (why?)  It would explain why the variable is displayed in the text label field but not the drop-down (and why the other drop-downs are displayed).

I'd be interested to understand why that happens and what to do to avoid it but otherwise I'll start to hack away at the code so that it works (re-checking submit on the second page and re-assigning the global variable is no value assigned).

[Scott_Parker · Accepted solution]

Set() doesn't always work the way you expect it to. If you only need the variables within the screen you're navigating to, I would recommend using context variables, instead. You can set them using the Navigate() function's optional argument, UpdateContextRecord.

[Anonymous]

Thanks for replying.  I'll accept as a solution although in the end I found other issues which meant it'd be easier to creating a new form than continuing to investigate this.

Thanks again.